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•We investigated saliency and priority modulation in multiple components of the orienting response in a pop-out paradigm. •Larger pupil responses were produced in the pop-out condition than in other control conditions after stimulus presentation. •Microsaccade direction was biased toward the pop-out item when it was the subsequent saccadic target. •The midbrain superior colliculus is coordinating these behaviors because of its central role in orienting behavior including pupil size and microsaccades. A salient stimulus can trigger a coordinated orienting response consisting of a saccade, pupil, and microsaccadic responses. Saliency models predict that the degree of visual conspicuity of all visual stimuli guides visual orienting. By presenting a multiple-item array that included an oddball colored item (pop-out), randomly mixed colored items (mixed-color), or single-color items (single-color), we examined the effects of saliency and priority (saliency + relevancy) on pupil size and microsaccade responses. Larger pupil responses were produced in the pop-out compared to the mixed-color or single-color conditions after stimulus presentation. However, the saliency modulation on microsaccades was not significant. Furthermore, although goal-relevancy information did not modulate pupil responses and microsaccade rate, microsaccade direction was biased toward the pop-out item when it was the subsequent saccadic target. Together, our results demonstrate saliency modulation on pupil size and priority effects on microsaccade direction during visual pop-out. [ABSTRACT FROM AUTHOR]